1、普通文件读写

文件样式

#client listener
listenip=172.18.111.180
listenport=20000
#monitor listener
monitorlistenip=0.0.0.0
monitorlistenport=8888
monitortoken=123
#http listener
httplistenip=0.0.0.0
httplistenport=12345
logfiledir=logs/
logfilename=chatserver
logbinarypackage=0
#mysql config
dbserver=172.18.111.180
dbuser=root
dbpassword=123456
dbname=flamingo

0、头文件

#ifndef __CONFIG_FILE_READER_H__
#define __CONFIG_FILE_READER_H__
#include <map>
#include <string>
class CConfigFileReader
{
public:
    CConfigFileReader(const char* filename);
    ~CConfigFileReader();
    char* getConfigName(const char* name);
    int setConfigValue(const char* name, const char*  value);
private:
    void  loadFile(const char* filename);
    int   writeFile(const char* filename = NULL);
    void  parseLine(char* line);
    char* trimSpace(char* name);
    bool                                m_load_ok;
    std::map<std::string, std::string>  m_config_map;
    std::string                         m_config_file;
};
#endif //!__CONFIG_FILE_READER_H__
//构造 解析
CConfigFileReader::CConfigFileReader(const char* filename)
{
    loadFile(filename);
}
CConfigFileReader::~CConfigFileReader()
{
}

1、文件打开

void CConfigFileReader::loadFile(const char* filename)
{
    m_config_file.clear();
    m_config_file.append(filename);
    FILE* fp = fopen(filename, "r");
    if (!fp)        
        return;
    char buf[256];
    for (;;)
    {
        char* p = fgets(buf, 256, fp);//每行读取256
        if (!p)
            break;
        size_t len = strlen(buf);
        if (buf[len - 1] == '\n')
            buf[len - 1] = 0;            // remove \n at the end
        char* ch = strchr(buf, '#');    // remove string start with #
        if (ch)
            *ch = 0;
        if (strlen(buf) == 0)
            continue;
        parseLine(buf);//逐行分析
    }
    fclose(fp);
    m_load_ok = true;
}

2、逐行分析

void CConfigFileReader::parseLine(char* line)
{
    char* p = strchr(line, '=');//分隔符
    if (p == NULL)
        return;
    *p = 0;
    char* key =  trimSpace(line);
    char* value = trimSpace(p + 1);
    if (key && value)
    {
        m_config_map.insert(std::make_pair(key, value));
    }
}

3、分析一行的key/value

char* CConfigFileReader::trimSpace(char* name)
{
    // remove starting space or tab
    char* start_pos = name;
    while ( (*start_pos == ' ') || (*start_pos == '\t') || (*start_pos == '\r'))
    {
        start_pos++;
    }
    if (strlen(start_pos) == 0)
        return NULL;
    // remove ending space or tab
    char* end_pos = name + strlen(name) - 1;
    while ( (*end_pos == ' ') || (*end_pos == '\t') || (*end_pos == '\r'))
    {
        *end_pos = 0;
        end_pos--;
    }
    int len = (int)(end_pos - start_pos) + 1;
    if (len <= 0)
        return NULL;
    return start_pos;
}

4、读写值

char* CConfigFileReader::getConfigName(const char* name)
{
    if (!m_load_ok)
        return NULL;
    char* value = NULL;
    std::map<std::string, std::string>::iterator it = m_config_map.find(name);
    if (it != m_config_map.end())
    {
        value = (char*)it->second.c_str();
    }
    return value;
}
int CConfigFileReader::setConfigValue(const char* name, const char* value)
{
    if(!m_load_ok)
        return -1;
    std::map<std::string, std::string>::iterator it = m_config_map.find(name);
    if(it != m_config_map.end())
    {
        it->second = value;
    }
    else
    {
        m_config_map.insert(std::make_pair(name, value));
    }
    return writeFile();
}

5、写文件

int CConfigFileReader::writeFile(const char* filename)
{
   FILE* fp = NULL;
   if(filename == NULL)
   {
       fp = fopen(m_config_file.c_str(), "w");
   }
   else
   {
       fp = fopen(filename, "w");
   }
   if(fp == NULL)
   {
       return -1;
   }
   //把map内的数据全部写入文件
   char szPaire[128];
   std::map<std::string, std::string>::iterator it = m_config_map.begin();
   for (; it != m_config_map.end(); it++)
   {
      memset(szPaire, 0, sizeof(szPaire));
      snprintf(szPaire, sizeof(szPaire), "%s=%s\n", it->first.c_str(), it->second.c_str());
      size_t ret =  fwrite(szPaire, strlen(szPaire),1,fp);
      if(ret != 1)
      {
          fclose(fp);
          return -1;
      }
   }
   fclose(fp);
   return 0;
}

6、使用

CConfigFileReader config("etc/chatserver.conf");
const char* logbinarypackage = config.getConfigName("logbinarypackage");

2、json文件读写

1、读文件

bool readJsonCfg(const char* filename, Json::Value* pRoot)
{
    Json::CharReaderBuilder builder;
    string errs;
    bool ret = false;
    pRoot->clear();
    ifstream ifs; // 
    ifs.open(filename);
    builder["collectComments"] = false;
    if (!parseFromStream(builder, ifs, pRoot, &errs)) // jsonRoot
    {
        printf("read file %s\n", errs.data());
        ret = false;
    }
    else
    {
        // printf("parse object type\n");
        ret = true;
    }
    ifs.close();
    return ret;
}

2、写文件

bool writeJsonCfg(const char* filename,const char* content, int len)
{
        FILE *f;
        f = fopen(filename, "w");
        if(!f)
        {
            cout << "file open error" << endl;
            return false;
        }
        fwrite(content, len, 1, f);
        fclose(f);
        return true;
}

3、c++ 流文件读写

4、打印

void PrintHexArray(const uint8* pArray, uint16 iLen)
{
    uint16 i = 0;
    for(i = 0; i < iLen; i++)
    {
        printf("%02X ", (uint8)pArray[i]);
    }
    printf("\n");
}
void PrintASCIIArray(const uint8* pArray, uint16 iLen)
{
    uint16 i = 0;
    for(i = 0; i < iLen; i++)
    {
        printf("%c", (uint8)pArray[i]);
    }
    printf("\n");
}